Field of the Invention
The invention relates to a method for integrating a traction motor and an inverter and an integrated system of traction motor and an inverter.
Description of the Related Art
As shown in FIGS. 1-3, an integrated power system of an existing electric car includes an independent traction motor 101 and an inverter 102. The traction motor 101 and the inverter 102 are independently and separately arranged and are in electric connection via a high-voltage power cable, a low-voltage signal harness, and a plurality of connectors 103. The inverter 102 includes: a control box 1021, and an IGBT module 1022, a driving board 1023, and a control board (MCU) 1024 that are disposed inside the control box 1021. A motor housing 1011 of the traction motor 101 is provided with a first cooling water channel. The bottom surface of the control box 1021 is provide with a second cooling water channel 1025. The first cooling water channel and the second cooling water channel 1025 are connected in series via a water pipe 104. However, the integrated power system has the following problems: 1) The traction motor and the inverter are independently and separately arranged, which results in too many wirings, troublesome connection, high production cost, and relatively large volume. 2) The traction motor and the inverter are connected by high-voltage cables, high-voltage signals produced by the high-voltage power cable and the IGBT module will affect normal operations of the driving board and the control board, thereby resulting in serious disturbance, and decreasing reliability and the operation efficiency of the motor controller. 3) A large number of components are disposed inside the inverter, connections among the components are complex, the wiring harnesses are too many, the production cost is high, connection errors prone to occur, and the reliability is low. 4) Both the traction motor and the motor controller utilize separate water cooling channels to dissipate heat, so that the heat dissipation performance of the integrated system is relatively low, the overall performance and the efficiency of the system are affected, and the service life and the reliability of the system are decreased.